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| author | Andreas Herrmann <andreas.herrmann3@amd.com> | 2008-06-10 16:05:18 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-06-12 10:14:22 +0200 |
| commit | 97cfab6ac4ddfda0d722393bbf46cc40bc332107 (patch) | |
| tree | 699f95483b968bfad891bca59ad46f74949543bc /arch | |
| parent | ee863ba7ab3d3ed8a9585d378aae69d1e3e9f1b4 (diff) | |
| download | blackbird-op-linux-97cfab6ac4ddfda0d722393bbf46cc40bc332107.tar.gz blackbird-op-linux-97cfab6ac4ddfda0d722393bbf46cc40bc332107.zip | |
x86: PAT: fix ambiguous paranoia check in pat_init()
Starting with commit 8d4a4300854f3971502e81dacd930704cb88f606 (x86:
cleanup PAT cpu validation) the PAT CPU feature flag is not cleared
anymore. Now the error message
"PAT enabled, but CPU feature cleared"
in pat_init() is misleading.
Furthermore the current code does not check for existence of the PAT
CPU feature flag if a CPU is whitelisted in validate_pat_support.
This patch clears pat_wc_enabled if boot CPU has no PAT feature flag
and adapts the paranoia check.
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kernel/cpu/addon_cpuid_features.c | 7 | ||||
| -rw-r--r-- | arch/x86/mm/pat.c | 11 |
2 files changed, 10 insertions, 8 deletions
diff --git a/arch/x86/kernel/cpu/addon_cpuid_features.c b/arch/x86/kernel/cpu/addon_cpuid_features.c index 0fbd06241e07..2df461f06a52 100644 --- a/arch/x86/kernel/cpu/addon_cpuid_features.c +++ b/arch/x86/kernel/cpu/addon_cpuid_features.c @@ -53,6 +53,9 @@ void __cpuinit init_scattered_cpuid_features(struct cpuinfo_x86 *c) #ifdef CONFIG_X86_PAT void __cpuinit validate_pat_support(struct cpuinfo_x86 *c) { + if (!cpu_has_pat) + pat_disable("PAT not supported by CPU."); + switch (c->x86_vendor) { case X86_VENDOR_INTEL: if (c->x86 == 0xF || (c->x86 == 6 && c->x86_model >= 15)) @@ -64,8 +67,6 @@ void __cpuinit validate_pat_support(struct cpuinfo_x86 *c) return; } - pat_disable(cpu_has_pat ? - "PAT disabled. Not yet verified on this CPU type." : - "PAT not supported by CPU."); + pat_disable("PAT disabled. Not yet verified on this CPU type."); } #endif diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c index 320d644a8107..65105b1195a3 100644 --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat.c @@ -76,14 +76,15 @@ void pat_init(void) return; /* Paranoia check. */ - if (!cpu_has_pat) { - printk(KERN_ERR "PAT enabled, but CPU feature cleared\n"); + if (!cpu_has_pat && boot_pat_state) { /* - * Panic if this happens on the secondary CPU, and we + * If this happens we are on a secondary CPU, but * switched to PAT on the boot CPU. We have no way to * undo PAT. - */ - BUG_ON(boot_pat_state); + */ + printk(KERN_ERR "PAT enabled, " + "but not supported by secondary CPU\n"); + BUG(); } /* Set PWT to Write-Combining. All other bits stay the same */ |
